92 THE NAUTILUS. 



tions through. Nacre livid or bright pink. Width 2 in. length 1 

 in. diam. | in. 



Habitat: Suwannee River, Madison Co., Florida. 



Remarks : A large series of this peculiar shell shows considerable 

 variation in strength of, and area covered by the plications, sharp- 

 ness of the umbonal ridge and color of nacre. It cannot, however, 

 be mistaken for any other species. Its natural place is between 

 Unio subtentus Say and Unio penicillatm Lea. We name it in 

 honor of our esteemed conchologist Mr. Bryant Walker of Detroit, 

 Mich. 



POLYGYRA FERRISSI n. sp. 



BY H. A. PILSBRY. 



Shell resembling Polygyra dentifera Binn. in size and general 

 form. Imperforate, thin, glossy, last two whorls of a very bright 

 chestnut color, becoming light green on the earlier whorls. Spire 

 very low, convex. Whorls 41, all rather convex, the first, minutely 

 rugose, granulate, following whorls of the spire slowly widening 

 arcuately striate and sparsely granulate, the granules oblong, 

 generally upon the strise ; last whorls rapidly widening, a trifle 

 constricted behind the peristome, very little descending in front, 

 sculptured with fine, rather low strise of growth and very fine, sub- 

 obsolete close spiral impressed lines; base very little impressed at 

 the center. Sutures well impressed throughout. Aperture oblique, 

 wide-orescentic ; peristome white, shading through pink to a broad 

 purple band at the margin, very broad and flatly reflexed, appressed 

 over and closing the umbilicus; parietal wall with a transparent 

 film between the lips, and bearing a small oblique tooth nearer to 

 the termination of the outer than to that of the basal lip. 



Alt. 13, greatest diam. 21-5, least 18 mm. 



Alt. 11, greatest diam. 20, least 16'5 mm. 



Klingman's Dome and Mirey Ridge, Great Smoky Mountains 

 (between Tenn. and N. C.). 



Mr. Jas. H. Ferris found this very beautiful Helix during his 

 summer journey in the Great Smoky range this year, with the 

 banded form of Polygyra Andrewsce, a very dark, unicolored form 

 of the same, P. Clarkii of extraordinary size, and other interesting 

 snails. 



P. Ferrissi is intermediate between several very distinct Helices. 

 It has the convex green and granulate inner whorls of P. sub- 

 palliata Pils., the fragile substance and flat, wide lip of P. dentifera 

 Binn., and the sculpture of the last whorl somewhat like P. appressa 

 perigrapta Pils. 



The combination of these characters, together with the deep, rich 

 reddish chestnut color of the body-whorl, emphatically negative a 

 reference of the specimens to any of these species. The half-grown 

 shell, 14 mm. diam., has an umbilicus 1 mm. wide and is very 

 obsoletely angular at the periphery. 



